Katarzyna Mastalerz, M.D.
Katarzyna Mastalerz, M.D. is a Hospitalist Physician in Denver, CO, registered under NPI 1861514275. This provider registers 2 separate taxonomy codes, which usually means they practise across more than one recognised specialty.
Getting there
The practice address on file is 1721 E 19TH AVE SUITE 520, Denver, CO 80218. We have not yet mapped what surrounds this office — parking, transit, and nearby pharmacies are added as our data collection reaches each location.
Credentials and Medicare
| Licence | State | Specialty |
|---|---|---|
| DR.0048931 | CO | Hospitalist Physician primary |
| 48931 | CO | Internal Medicine Physician |
This provider holds licence DR.0048931 issued in CO. A licence number in NPPES reflects what was filed at registration — it does not confirm the licence is still active today.
- Status
- Approved
- Provider type
- Practitioner - Hospitalist
- PAC ID
- 5092831909
- Enrollment ID
- I20100929000180
Medicare enrolment is recorded as approved under the provider type Practitioner - Hospitalist. Being enrolled means the provider can bill Medicare; it does not tell you whether they are currently accepting new Medicare patients. Call the office to confirm.
What Hospitalist covers
Hospitalists are physicians whose primary professional focus is the general medical care of hospitalized patients. Their activities include patient care, teaching, research, and leadership related to Hospital Medicine. The term 'hospitalist' refers to physicians whose practice emphasizes providing care for hospitalized patients. NUCC Health Care Provider Taxonomy, code 208M00000X
All registered taxonomy codes
This provider registers 2 taxonomy codes. The primary code is what appears on most claims; the others record additional recognised specialties.
| Code | Specialty | Licence | State | |
|---|---|---|---|---|
| 208M00000X | Hospitalist Physician | DR.0048931 | CO | primary |
| 207R00000X | Internal Medicine Physician | 48931 | CO |
The taxonomy records how the provider classifies their own practice. It does not confirm which conditions they currently treat, whether they are accepting new patients, or which insurance they take — call the office for that.
Full NPPES record
An NPI-1 identifies a single person. It stays with the clinician for life, even if they move practice or change state, which is why the address on file can lag behind where they actually work today.
| NPI | 1861514275 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Apr 4, 2007 |
| Last updated | Mar 15, 2023 |
| Status | Active |
| Sole proprietor | No |
| Credential | M.D. |
| Practice address |
1721 E 19TH AVE SUITE 520 Denver, CO 80218 (303) 869-2440 Fax (303) 869-2544 |
| Mailing address |
PO BOX 110429 Aurora, CO 80042 |
Number check
How the check works, step by step
Every NPI carries a Luhn check digit — the same scheme used on credit cards. CMS prefixes the number with 80840 before computing it, which marks it as a US health identifier.
| Digit | 8 | 0 | 8 | 4 | 0 | 1 | 8 | 6 | 1 | 5 | 1 | 4 | 2 | 7 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 8 | 3 | 1 | 1 | 1 | 8 | 2 | 5 |
Sum = 55 · next multiple of 10 = 60 · check digit = 5 · actual last digit = 5
A valid check digit only means the number is well-formed. It does not mean the provider is licensed, active, or in good standing — those are separate questions answered by the sections above.